I'm buying a 04.5 duramax LLY need to know what to look for when I'm test driving it how it response is it good pull? He has efi live tuning on the fly 5 tunes for $500 for each tune the truck has 173000 lifted 6" with 35s" need to know what I should check or check for

 

I'd inspect that thing like a hawk with tunes and lifted...that things been rode hard and I'm sure them pistons are blue!! Ask him the basics service records tranny fluid changes if tcase is original( these are known for pump rub) look over the front end ball joints etc original injectors and see if it has a fuel filter upgrade ....the usual stuff make sure coolant doesn't bubble in resovoir and that there is no diesel fuel in the oil.

 

alright the truck has sinister egr delete 4" diamond eye cat less and muffler delete ppe race fuel valve new injectors fass 150 lift pump upgraded cp3 dsp5 switch to change tune on the fly 5 efi live tunes largest tune on stage 5 is a plus 225hP tune do you think it's a good buy for 12800 needs cab corners and rockets